I guess what you're describing is an issue of selective enforcement.
If you believe you've been victimized and want to sue, contact a real attorney who will then analyze the situation and advise you (as to) whether or not you have a case.
This will be a matter of "he said/she said".......
Otherwise, you might simply wanna chalk it up to experience and put it under your hat in case there's a next time..... And beware of those specific cops in case they actually have a specific "hard on" for you or your friends.....
FYI: nearly every young person believes that ALL cops do have a specific hard on for them and their friends....
If I have missed your point altogether, please forgive me...I'm just trying to help.
D